title: Radiation dose of the P-glycoprotein tracer 11C-laniquidar.
abstract: Resistance to current drug therapy is an important issue in the treatment of epilepsy. Inadequate access of central nervous system drugs to their targets in the brain may be caused by overexpression or overactivity of multidrug transporters, such as P-glycoprotein (P-gp), at the blood-brain barrier. Laniquidar, an inhibitor of P-gp, has been labeled with (11)C for use in PET studies of P-gp expression in humans. Given potential interspecies differences in biodistribution, the purpose of this study was to ensure safe use of (11)C-laniquidar by determining the dosimetry of (11)C-laniquidar using whole-body PET studies.
  
  
  METHODS
  Six healthy volunteers were subjected to a series of 10 whole-body PET scans within approximately 70 min. Five blood samples were taken during the series.
  
  
  RESULTS
  High uptake of (11)C-laniquidar was seen in liver, spleen, kidneys, and lung, whereas brain uptake was low. The effective dose for (11)C-laniquidar was 4.76 ± 0.13 and 3.69 ± 0.01 μSv·MBq(-1) for women and men, respectively.
  
  
  CONCLUSIONS
  Biodistribution and measured effective dose indicate that (11)C-laniquidar is a safe tracer for PET imaging, with a total dose of about 2 mSv for a brain PET/CT protocol.
authors.affiliation: Departments of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Andrey
authors.initials: A
authors.lastname: Postnov
authors.forename: Femke E
authors.initials: FE
authors.lastname: Froklage
authors.forename: Arthur
authors.initials: A
authors.lastname: van Lingen
authors.forename: Jaap C
authors.initials: JC
authors.lastname: Reijneveld
authors.forename: N Harry
authors.initials: NH
authors.lastname: Hendrikse
authors.forename: Albert D
authors.initials: AD
authors.lastname: Windhorst
authors.forename: Robert C
authors.initials: RC
authors.lastname: Schuit
authors.forename: Jonas
authors.initials: J
authors.lastname: Eriksson
authors.forename: Adriaan A
authors.initials: AA
authors.lastname: Lammertsma
authors.forename: Marc C
authors.initials: MC
authors.lastname: Huisman
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D000328:Adult; D001552:Benzazepines / Q000493:pharmacokinetics; D002250:Carbon Radioisotopes; D005260:Female; D006801:Humans; D008297:Male; D011804:Quinolines / Q000493:pharmacokinetics; D011829:Radiation Dosage; D011849:Radioactive Tracers; D011874:Radiometry
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D001552:Benzazepines; D002250:Carbon Radioisotopes; D011804:Quinolines; D011849:Radioactive Tracers; C411474:laniquidar
keywords: 11C-laniquidar; P-glycoprotein; PET; dosimetry; multidrug transporter